Hair has many functions. It protects the skin, traps dust, and can be used for aesthetic purposes. It can also express our personal style and tastes. Although hair is a complex structure, it is an essential part of our body. It covers almost every surface. Here’s an overview of the anatomy and function of human tresses. Its various types are: long, thin, and curly. Interestingly, most of our tresses are living, so they can regenerate and continue to serve their function.
A person’s hair is composed of three layers: the cuticle, cortex, and medulla. The cuticle layer contains millions of polypeptide chains, which are held together by side bonds. These bonds are what contribute to the strength and elasticity of our hair. The hydrogen and salt bonds in our hair are broken when exposed to heat and water. A change in pH will affect these bonds. If hair is trimmed or damaged, it can result in a bald spot.
The cortex layer contains millions of polypeptide chains. These chains are linked by side bonds, which are triggered by the sympathetic nervous system. The arrector pili then contracts, making the external hair shaft “stand up” and traps a layer of air on the surface. The result is a feeling of warmth and a sexy look. The side bonds are also responsible for the appearance of goose bumps in animals. The bigger the animal, the larger the goose bumps.
A person’s hair is made up of three different layers: the cuticle, the cortex, and the medulla. The cuticle cells are square and flat. They attach tightly to the cortex cells, and move up the hair shaft. The overlapping of the three layers contributes to a hair’s shape. The medulla, or top part, is made up of keratin. The material is used in nails, hoofs, and feathers, and is extremely durable.
The origin of hair is unknown, but it has been found that synapsids shared a common ancestor with modern mammals. Its ancestors did not have hair at that time, but some of them had scattered bristles on their skins. These animals are the oldest known examples of humans with a distinct sex identity and a variety of body types. The oldest species of hair have been identified as the earliest in the fossil record, which dates back to around 299 million years ago.
The origin of hair is unknown, but it is possible that the earliest animals had hair. These creatures exhibited a variety of characteristics, such as cuticle, cortex, and medulla. Unlike crocodiles, they had four layers of scutes and a thin layer of cuticle cells. They are flat, square, and have a transverse axis. Further, they had distinct faces, and they could not have moved from one part of the body to another.